/Engine/Source/Runtime/AppFramework/Public/Widgets/Colors/SColorThemes.h
SThemeColorBlocks are Color Blocks which point to a Color in a ColorTheme. They can be dragged and dropped, and clicking on one in the Color Picker will give the color that they point to.
class SThemeColorBlock : public [SCompoundWidget](API\Runtime\SlateCore\Widgets\SCompoundWidget)